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Full text of "Alaskan glacier studies of the National Geographic Society in the Yakutat Bay, Prince William Sound and lower Copper River regions"

374                                 ALASKAN GLACIER STUDIES
Glaciers of Applegate Arm. The glaciers of Applegate Ann are Cotterell, Taylor, and Claremont Glaciers on the western side, and Langdon, Kings, Applegate, Falling, and smaller ice tongues on the eastern side. The ice tongues of the western side of Apple-gate Arm are fed from the snowfields which also supply ice to Tebenkof Glacier and the ice tongues at the head of Blackstone Bay. Several of these glaciers were mapped by Applegate, who went close to them when he discovered this fiord, in 1887. They were surveyed more in detail by Grant and Higgins in 1908 (Fig. 55), but up to the present time, with the exception of a brief note, quoted below, they have published no description of the outwash gravel fans and barren zones, which they mapped, together with a terminal moraine of Claremont Glacier. They stated that when they visited this fiord they did not examine in detail the glaciers on its western side.
"South of the central part and east of the southern part of Port Nellie Juan is a snow-field of unknown but considerable extent. Several glaciers flow north and west from this field, and . . . Falling Glacier reaches tide water. On the west side of the southern part of the port (Applegate Arm) are other glaciers, one of which, the Taylor, reaches tide water. The head (of Applegate Arm) is shallow and the waters very muddy. This is due to streams from the adjoining glaciers, and especially to ... Kings River, entering the head of the port . . . charged with glacial silt (coming) from one of the largest ice covered areas of the Kenai Peninsula."
The National Geographic Society's party saw only Cotterell Glacier in 1910 and this at a considerable distance, so we have no information as to the behavior of the glaciers of Applegate Arm from 1908 to 1910. The largest glacier of Applegate Arm, which supplies the water of Kings River, has not yet been mapped or studied.
Qlaciation of Port Nellie Juan. In this broad, deep fiord the evidence of the former extension of the glaciers is clear, the glaciated fiord walls, especially the precipitous northwestern side of Blue Fiord, the plunking of the well-jointed granite of the rock hill at the terminus of Nellie Juan Glacier and on Nichols Island, and the glacial striae, making it plain that the whole fiord was formerly filled by an ice tongue which flowed into Prince William Sound.
Glacial deposits are of small extent, and the fairly thick, mature growth of vegetation (for example, on Nichols Island and on the mainland near Nellie Juan Glacier) makes it clear that the last greatly expanded stage of these glaciers was more than a century ago.
The small barren zones near Nellie Juan and Ultramarine Glaciers, and near the ice tongues of Applegate Arm, mapped and described by Grant and Higgins, are interpreted as evidence of a slight advance, two decades or more ago, similar to the advances in the fiords to the north.
The extent to which glacial erosion has deepened and otherwise modified the fiord is likewise unknown. Judging by the absence of many reefs and of kelp away from the shores, it is assumed that here, as elsewhere, the fiord has been deepened throughout by glacial erosion.
General Description. The entrance to Icy Bay, which is connected with Prince William Sound both to the north and south by a broader fiord called Knight Island Passage, is between Chenega Island and Point Countess. The outer part of Icy Bay (PL XCffl) trends northwest-southeast for 8 miles, with a width of 3 to 4 miles; while the inner